Blender 2.8 (Python) - manipulating the camera for resized objects
So basically you want to have a plane or area that should be included in camera view? 

There are few way to include different area size: 


Actually move camera to get a better cover of view. 
Adjust the camera sensor size directly. 
Adjust FOV setting for wider view. 


For the first one: view_selected is already include in Blender.

My naive solution is to actually create a mesh indicated your desired area and select it, view_selected it and move camera to here. But the size of the render view might cut up some places since the view won't be entire include in camera. So the things get more complicate if using existed function. Then writing some math function will be faster for sure.

You only need to calculate those coordinates from your points, using camera view coordinate system. Then other thing should be easily done